Phenergan (Promethazine) — Complete Guide

• INN (International Nonproprietary Name): Promethazine hydrochloride
• Brand Names Available In Australia: Phenergan — Tablets: 10mg, 25mg (Blister packs of 25/50); Elixir: 1mg/mL (100mL bottle)
• ATC Code: R06AD02
• Forms & Dosages: Tablets 10mg and 25mg; Elixir 1mg/mL in 100mL bottle; suppositories (12.5mg, 25mg, 50mg) are less commonly available or discontinued by some suppliers
• Manufacturers In Australia: sanofi-aventis australia pty ltd
• Registration Status In Australia: Registered with the TGA (AUST R 80159 and 80160 for tablets; AUST R 61576 for elixir)
• OTC / Rx Classification: Prescription medication (Rx) in most countries including Australia

Latest Research Highlights

Worried about whether promethazine still has a role after newer antiemetics arrived?

Recent Australian and international literature from 2022–2025 continues to position promethazine as an effective sedating antihistamine for acute nausea, motion sickness and short-term sedation.

Safety reporting concentrates on paediatric respiratory depression in children under two and anticholinergic burden in older adults.

Australian pharmacoepidemiology using TGA adverse-event reports and hospital databases shows stable adult use and declining prescriptions in children under two after strengthened warnings.

International systematic reviews from 2022–24 report moderate-quality evidence for antiemetic efficacy versus placebo in motion sickness and peri-operative sedation, with study heterogeneity noted.

Comparative randomised trials versus modern non-sedating antihistamines are limited.

Key product facts remain: ATC code R06AD02 and common Australian formulations are tablets 10mg/25mg and elixir 1mg/mL.

TGA registrations AUST R 80159, 80160 and 61576 confirm authorised supply in Australia.

Suggested visuals for clinicians: a forest plot of antiemetic effect sizes and an evidence-grade summary comparing efficacy and safety.

Clinical Effectiveness In Australia

Can promethazine still stop nausea or prevent motion sickness reliably?

Australian clinicians commonly use Phenergan for motion sickness, acute allergic reactions when sedation is acceptable, and nausea or vomiting not responding to first-line antiemetics.

PBS coverage is limited for promethazine specifically, so many prescriptions are private and this affects access and cost to patients.

TGA-monitored outcomes emphasise symptom relief but caution about sedative burden in routine care.

Real-world data from emergency departments show decreased repeat presentations for vertigo or motion sickness when promethazine is used appropriately as a single or short course.

Compared with cetirizine or loratadine, promethazine gives superior sedation but similar antihistaminic control for allergic symptoms when sedation is acceptable.

For antiemesis, promethazine is often chosen when ondansetron or metoclopramide are unsuitable or contraindicated.

Indications And Expanded Uses

What is promethazine licensed for and when might a prescriber use it off-label?

Approved TGA indications in Australia reflect antihistamine and antiemetic roles including allergic conditions where sedation is acceptable, motion sickness prevention, symptomatic treatment of nausea and vomiting, and short-term pre-operative sedation.

Common off-label uses in Australian practice include adjunctive management of severe pruritus, use as a sedative in palliative care, and short-term insomnia when alternatives are limited.

Off-label use should have specialist oversight and documented informed consent in clinical records.

Pediatric use is limited; promethazine is contraindicated under two years due to risk of fatal respiratory depression and is dose-limited for older children.

• Approved: Motion sickness, symptomatic nausea/vomiting, allergic reactions where sedation is acceptable, short-term pre-op sedation.
• Common Off-Label: Severe pruritus adjunct, palliative sedation, short-term insomnia under specialist guidance.
• Contraindicated: Children under 2 years, comatose patients, severe respiratory depression, hypersensitivity to phenothiazines.

Available Australian dosing formats — tablets 10mg/25mg and elixir 1mg/mL — support oral and paediatric dose adjustments when prescribed.

Composition And Brand Landscape

Which brands and strengths should pharmacists expect to stock in Australia?

The active ingredient is promethazine hydrochloride, sold predominantly in Australia under the Phenergan brand name.

Packaging commonly seen in Australian pharmacies includes tablets 10mg and 25mg in blister packs of 25 or 50, and elixir 1mg/mL in 100mL bottles.

Sanofi-aventis australia pty ltd is the local manufacturer for Phenergan in Australia.

International brands include Avomine, Lergigan and Prothiazine, and some supplies overseas include suppositories and other forms that are less common locally.

Pharmacists should distinguish sedating promethazine products from non-sedating antihistamines when counselling patients.

Contraindications And Special Precautions

Who must not take promethazine and what should pharmacists warn about?

Absolute contraindications include known hypersensitivity to promethazine or other phenothiazines, comatose states, severe respiratory depression and children under two years because of risk of fatal respiratory depression.

Relative cautions apply to elderly patients because of increased sedation, confusion and hypotension risk.

Other cautionary states include severe hepatic or renal impairment, seizure disorders, narrow-angle glaucoma, prostatic hypertrophy and urinary retention.

Pregnancy use is only advised if the benefit outweighs the risk because promethazine crosses the placenta and can cause neonatal sedation.

• Everyday Precautions: Avoid driving or operating machinery until effects are known.
• Workplace Advice: Counsel miners and heavy machinery operators about sedation risk and safety implications.
• Pharmacist Checklist: Check contraindications, interactions, monitor anticholinergic signs and adjust dose for hepatic/renal impairment.

TGA warnings and local governance suggest restricting use in aged-care without regular review.

Dosage Guidelines

What doses are used in adults, children and older people in Australia?

Standard adult dosing aligns with product information: for allergic conditions 10–25mg at night or 10mg two to three times daily.

For motion sickness typical adult dosing is 25mg the night before travel or 1–2 hours prior to exposure.

For nausea and vomiting adults commonly use 25–50mg with repeats every four to six hours if required.

Tablets are available as 10mg and 25mg and the elixir is 1mg/mL to allow flexible paediatric dosing.

Children under two years should not receive promethazine because of the risk of severe respiratory depression.

Older children have weight-based suggestions (for example 5–15mg at night), but specialist advice is recommended.

Avoid chronic nightly use for insomnia because of tolerance and anticholinergic harms.

Interactions Overview

Do other medicines or alcohol make promethazine more dangerous?

Promethazine has clinically important interactions with other CNS depressants such as alcohol, opioids and benzodiazepines and these cause additive sedation and respiratory depression.

Anticholinergic synergy occurs with tricyclic antidepressants, antipsychotics and other antihistamines leading to dry mouth, urinary retention and confusion.

Concomitant MAOI use may potentiate adverse reactions and caution is needed with drugs that prolong the QT interval in susceptible patients.

Alcohol markedly increases sedation; caffeine will not counteract anticholinergic effects and may mask sedation.

Pharmacists should use dispensing software interaction checks and advise patients to notify all prescribers.

Cultural Perceptions And Patient Habits

What do patients in Australia think about Phenergan?

Many Australians view Phenergan as a reliable motion-sickness remedy and a familiar sedating antihistamine, especially older generations and rural travellers.

Consumer forums and pharmacy consultations show strong trust in pharmacist advice and price sensitivity which drives comparison shopping at major chains.

Telehealth and e-prescriptions are popular for convenience and allow patients in remote areas to obtain promethazine when needed.

In Indigenous health settings culturally safe prescribing and careful communication about sedation and occupational impacts are essential.

Stigma around sedation at work, particularly in mining and transport sectors, can lead to patients under-dosing or avoiding effective treatment out of job-safety concerns.

• Regional Access: Rural pharmacies may stock limited quantities and may supply single-dose regimens for travellers.
• Patient Habits: Older patients often prefer Phenergan for overnight relief; daytime allergy control is more likely with non-sedating agents.

Availability And Pricing Patterns

Where can patients buy Phenergan and what will it cost?

Phenergan (promethazine hydrochloride) is registered with the TGA and commonly available in tablets 10mg/25mg and elixir 1mg/mL in Australia.

Retail channels include major chains such as Chemist Warehouse, Priceline, TerryWhite Chemmart, independent pharmacies and online pharmacies offering telehealth e-prescriptions.

PBS listing is limited so many prescriptions are private and price comparisons show variance between discount chain promotions and independent pharmacy fees.

Rural pharmacies may have more frequent out-of-stock events and online pharmacies can bridge gaps but require a valid prescription.

For travellers, common pack sizes are blister 25/50 tablets or 100mL elixir bottles which affect cost and customs rules for carrying medicines interstate or overseas.

In our online pharmacy, phenergan is available without a prescription, with discreet delivery to Australia in 5-14 days.

Comparable Medicines And Preferences

Should a patient choose promethazine or an alternative antihistamine?

Alternatives include first-generation antihistamines such as chlorphenamine and diphenhydramine and second-generation non-sedating agents like cetirizine and loratadine for allergy control.

For nausea alternatives include ondansetron or metoclopramide depending on the cause and contraindications.

Pros of promethazine are potent sedation and antiemetic benefit which can be useful for travel and pre-op sedation.

Cons include higher anticholinergic risk and pronounced sedation compared with cetirizine or loratadine which are preferred for daytime allergy control.

• When To Prefer Promethazine: Overnight dosing, single-dose travel sleep and when sedation is desired.
• When To Prefer Alternatives: Daytime allergy control, long-term therapy, and in patients where anticholinergic burden is a concern.

PBS availability of subsidised alternatives often guides long-term prescribing choices toward safer, non-sedating antihistamines.

Frequently Asked Questions

Can I take Phenergan and drink alcohol?

No.

Alcohol markedly increases sedation and respiratory depression risk and should be avoided until effects are known.

Is Phenergan on the PBS?

Generally no.

Phenergan is usually prescribed privately and PBS coverage is limited so expect out-of-pocket costs in many cases.

Can children take Phenergan?

Not under two years.

Children under two years are contraindicated because of the risk of fatal respiratory depression and older children require weight-based dosing and clinician oversight.

Can I use Phenergan for chronic insomnia?

No, it is not recommended.

Chronic use risks tolerance, anticholinergic harms and dependency; short-term use only is the standard recommendation.

Available formulations commonly in Australia are tablets 10mg and 25mg and elixir 1mg/mL in 100mL.

Guidelines For Proper Use

How should pharmacists counsel patients who receive promethazine?

Begin by confirming the indication and checking age and absolute contraindications such as children under two years and hypersensitivity to phenothiazines.

Review current medications for interactions, especially CNS depressants and anticholinergic agents.

Advise on dose and route — tablet or elixir 1mg/mL — and explain common side effects including sedation and dry mouth.

Warn patients not to drive, operate machinery or drink alcohol until they know how promethazine affects them.

For elderly and Indigenous patients consider lower starting doses, reassess anticholinergic burden and provide culturally safe communication.

• Step 1: Confirm indication and age.
• Step 2: Review interactions and current medicines.
• Step 3: Explain dosing, side effects and safety actions.
• Step 4: Document counselling and encourage TGA adverse-event reporting if needed.

Provide a short patient handout summarising what to expect, what to avoid and when to seek help.

Delivery Across Australia